I started this new thread because I didnt want this "buried" in my Mainline build questions....
OK, I have 12+ headamps, three Dacs, a zillion tubes, and several media player/servers etc..as well as having a dozen headphones
of all types over the past few years.
My tastes have driven me to Beyerdynamics T90's + T1's, yes even with those mediocre reviews about their being shrill etc...
Most of the time I find the source material and how its recorded and mixed has more to do with this shrill sound than the transducer itself with the Beyers.
That said I spend a lot of time looking for recordings that are indeed the best of the best....and stopped trying to find a setup that will fix something that was done crappy with
the actual recording...no amount of eq'ing etc can fix these things IMO.
So the MAINLINE !!
It took me a week of 4-6 hours to complete. Taking my time, chceking all the solder joints, measuring resistors, walking away and checking parts placement and directivity etc..
I actually found one resistor in the wrong location on the c4S boards! Glad I found that....the only confusing part to "ME" was these smaller pc boards, you build two of them clearly
stated in the instructions, but they install in the A side and C side exactly upside down from each other....so just be careful here...maybe its just yours truly!! LOL.
The kit had 49.9K resistors instead of 49.9 ohm resistors, a missing fiber shoulder washer, and missing 4 of the larger #8 screws that hold down the middle power reg board.
Thanks to Josh and the Queen Bee in getting this sorted out, it was a long wait here!! But it was worth it!
The tubes glowed first time, voltage checks were spot on and the biasing was set to 145 volts....with the pots in the middle of their range, the initial volts showed 180 volts or so.
There was a small high frequency noise when first turned on with headphones, some of my less expensive ATH M50's...but after a fw minutes warmup it went away..probably those tubes
waking up for the first time!..My 12AU7 has CONN on it...must be a old Conn Organ variety! Very musical!! Ha!
I checked all the inputs, switches less the balanced headphone jack, my cans are all SE.
The fit into the locking SE jack is tight, firm, etc and take some effort to remove, I imagin over time this will loosed up somewhat.
The 4 coats of the Tung Oil high gloss loks great to me, smooth and very nice IMO.
So how does it sound?
First impressions, subjectively tells me this is indeed a very, very wonderful amp.
Musical, with well recorded stuff its magical with my T1V2's...some complain about the soundstage of these Beyers, but OMG its really
very good with this amp. (Am driving it with a Schitt MB Bimby dac). I will play with the other dacs I have in the coming days.
From listening to my Crack w/speedball and Schitt Vahalla 2 (OTL), I am experiencing a new level of listening pleasure....no doubt about it...
Open, Airy, tonality, all those glittering adjectives apply here....not syrupy to me at all....whats in the music comes out, good and bad.
I like many of you probably have some really stellar music, that we like and is recorded and mixed very well....and this stuff really shines.
Seeing into the music, tonality and soundstage with this amp is superlative.
I have not heard these T1's sound as good or perform as well as with this amp period.
I am glad we went thru the Crack stage, but if I had to do it all over again I would just jump to the Mainline and forget looking for something better..
This amp to is that good...
Well done Bottlehead!!
Alex
